Abstract 1322: Maximizing the therapeutic potential of SHP2 inhibition with rational combination strategies in tumors driven by aberrant RAS-MAPK signaling

AbstractChronic myeloid leukemia (CML) is characterized by the accumulation of malignant and immature white blood cells which spread to the peripheral blood and other tissues/organs. Despite the fact that current tyrosine kinase inhibitors (TKIs) are capable of achieving the complete remission by reducing the tumor burden, severe adverse effects often occur in CML patients treated with TKIs. The differentiation therapy exhibits therapeutic potential to improve cure rates in leukemia, as evidenced by the striking success of all-trans-retinoic acid in acute promyelocytic leukemia treatment. However, there is still a lack of efficient differentiation therapy strategy in CML. Here we showed that MPL, which encodes the thrombopoietin receptor driving the development of hematopoietic stem/progenitor cells, decreased along with the progression of CML. We first elucidated that MPL signaling blockade impeded the megakaryocytic differentiation and contributed to the progression of CML. While allogeneic human umbilical cord-derived mesenchymal stem cells (UC-MSCs) treatment efficiently promoted megakaryocytic lineage differentiation of CML cells through restoring the MPL expression and activating MPL signaling. UC-MSCs in combination with eltrombopag, a non-peptide MPL agonist, further activated JAK/STAT and MAPK signaling pathways through MPL and exerted a synergetic effect on enhancing CML cell differentiation. The established combinational treatment not only markedly reduced the CML burden but also significantly eliminated CML cells in a xenograft CML model. We provided a new molecular insight of thrombopoietin (TPO) and MPL signaling in MSCs-mediated megakaryocytic differentiation of CML cells. Furthermore, a novel anti-CML treatment regimen that uses the combination of UC-MSCs and eltrombopag shows therapeutic potential to overcome the differentiation blockade in CML.

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Skullcapflavone II Suppresses TNF-α/IFN-γ-Induced TARC, MDC, and CTSS Production in HaCaT Cells

International Journal of Molecular Sciences ◽

10.3390/ijms22126428 ◽

2021 ◽

Vol 22 (12) ◽

pp. 6428

Author(s):

Hanon Lee ◽

Dong Hun Lee ◽

Jang-Hee Oh ◽

Jin Ho Chung

Keyword(s):

P38 Mapk ◽

Therapeutic Potential ◽

Inflammatory Diseases ◽

Mapk Signaling ◽

Hacat Cells ◽

Protein Levels ◽

Tnf Α ◽

Ifn Γ ◽

Mapk Signaling Pathways ◽

Pro Inflammatory Cytokines

Skullcapflavone II (SFII), a flavonoid derived from Scutellaria baicalensis, has been reported to have anti-inflammatory properties. However, its therapeutic potential for skin inflammatory diseases and its mechanism are unknown. Therefore, this study aimed to investigate the effect of SFII on TNF-α/IFN-γ-induced atopic dermatitis (AD)-associated cytokines, such as thymus- and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC). Co-stimulation with TNF-α/IFN-γ in HaCaT cells is a well-established model for induction of pro-inflammatory cytokines. We treated cells with SFII prior to TNF-α/IFN-γ-stimulation and confirmed that it significantly inhibited TARC and MDC expression at the mRNA and protein levels. Additionally, SFII also inhibited the expression of cathepsin S (CTSS), which is associated with itching in patients with AD. Using specific inhibitors, we demonstrated that STAT1, NF-κB, and p38 MAPK mediate TNF-α/IFN-γ-induced TARC and MDC, as well as CTSS expression. Finally, we confirmed that SFII significantly suppressed TNF-α/IFN-γ-induced phosphorylation of STAT1, NF-κB, and p38 MAPK. Taken together, our study indicates that SFII inhibits TNF-α/IFN-γ-induced TARC, MDC, and CTSS expression by regulating STAT1, NF-κB, and p38 MAPK signaling pathways.

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Rational combination strategies to enhance venetoclax activity and overcome resistance in hematologic malignancies

Leukemia & Lymphoma ◽

10.1080/10428194.2017.1366999 ◽

2017 ◽

Vol 59 (6) ◽

pp. 1292-1299 ◽

Cited By ~ 5

Author(s):

Steven Grant

Keyword(s):

Hematologic Malignancies ◽

Combination Strategies ◽

Rational Combination

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Chirality-Dependent Anti-Inflammatory Effect of Glutathione after Spinal Cord Injury in an Animal Model

Pharmaceuticals ◽

10.3390/ph14080792 ◽

2021 ◽

Vol 14 (8) ◽

pp. 792

Author(s):

Seong-Jun Kim ◽

Wan-Kyu Ko ◽

Gong-Ho Han ◽

Daye Lee ◽

Yuhan Lee ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Therapeutic Potential ◽

Specific Interaction ◽

Mapk Signaling ◽

Mitogen Activated Protein Kinase ◽

Secondary Damage ◽

Cord Injury ◽

Mitogen Activated Protein ◽

Pro Inflammatory Cytokines

Neuroinflammation forms a glial scar following a spinal cord injury (SCI). The injured axon cannot regenerate across the scar, suggesting permanent paraplegia. Molecular chirality can show an entirely different bio-function by means of chiral-specific interaction. In this study, we report that d-chiral glutathione (D-GSH) suppresses the inflammatory response after SCI and leads to axon regeneration of the injured spinal cord to a greater extent than l-chiral glutathione (L-GSH). After SCI, axon regrowth in D-GSH-treated rats was significantly increased compared with that in L-GSH-treated rats (*** p < 0.001). Secondary damage and motor function were significantly improved in D-GSH-treated rats compared with those outcomes in L-GSH-treated rats (** p < 0.01). Moreover, D-GSH significantly decreased pro-inflammatory cytokines and glial fibrillary acidic protein (GFAP) via inhibition of the mitogen-activated protein kinase (MAPK) signaling pathway compared with L-GSH (*** p < 0.001). In primary cultured macrophages, we found that D-GSH undergoes more intracellular interaction with activated macrophages than L-GSH (*** p < 0.001). These findings reveal a potential new regenerative function of chiral GSH in SCI and suggest that chiral GSH has therapeutic potential as a treatment of other diseases.

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Abstract 234: Transcriptional Profiling of Neuregulin-Induced Myocardial Recovery After Infarction in Rats and Swine

Circulation Research ◽

10.1161/res.111.suppl_1.a234 ◽

2012 ◽

Vol 111 (suppl_1) ◽

Author(s):

Cristi L Galindo ◽

Abigail Murphy ◽

Michael Hill ◽

John Cleator ◽

Ehab Kasasbeh ◽

...

Keyword(s):

Heart Failure ◽

Therapeutic Potential ◽

Transcriptional Profiling ◽

Mapk Signaling ◽

Left Ventricular ◽

Experimental Myocardial Infarction ◽

Human Heart Failure ◽

Cardiovascular Tissue ◽

And Function ◽

Vehicle Treated Control

Neuregulin-1 (NRG-1) mediates cell-cell interactions and is a critical growth and developmental signaling molecule in the heart. We have been examining whether the recombinant NRG-1 isoform known as glial growth factor 2 (GGF2) has therapeutic potential for heart failure. In rats and swine with experimental myocardial infarction we have found that GGF2 treatment improves myocardial function and limits progressive myocardial remodeling. To understand potential mechanisms for this effect, we compared gene expression in these animals using microarrays. In rats we compared Sham operated, MI treated with vehicle, and MI treated with GGF2 at a single dose. We found that GGF2 treatment was associated with correction of mitochondrial and metabolic genes altered by MI compared to Sham-operated rats. When compared to 9 published datasets of ∼400 samples from rodents and human heart failure, we identified 563 genes associated with heart failure that were also reversed in expression in response to GGF2. Ingenuity pathway analysis demonstrated clusters of genes associated with energy production and cardiovascular tissue development as particularly enriched in GGF2-treated versus untreated MI rats. In swine our analysis was confined to animals with MI +/- GGF2 treatment at two doses. There were 527 genes altered by GGF2 at both doses compared to untreated controls, with a clear GGF2 dose response. Transcripts altered in response to GGF2 treatment were mainly those associated with extracellular matrix structure and function, MAPK signaling, and p53-mediated apoptosis. Electron microscopy of remote infarct left ventricular tissue from swine confirmed extreme morphological differences in mitochondria from GGF2-treated and vehicle-treated control pigs. Most striking was recovery of intercalated discs in response to GGF2, compared to severe disruption of intercalated disc structures in vehicle-treated control animals.

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Overactive IGF1/Insulin Receptors and NRASQ61R Mutation Drive Mechanisms of Resistance to Pazopanib and Define Rational Combination Strategies to Treat Synovial Sarcoma

Cancers ◽

10.3390/cancers11030408 ◽

2019 ◽

Vol 11 (3) ◽

pp. 408 ◽

Cited By ~ 3

Author(s):

Cinzia Lanzi ◽

Laura Dal Bo ◽

Enrica Favini ◽

Monica Tortoreto ◽

Giovanni Beretta ◽

...

Keyword(s):

Cell Line ◽

Synovial Sarcoma ◽

Molecular Mechanisms ◽

Soft Tissue Sarcomas ◽

Insulin Receptors ◽

Mek Inhibitor ◽

Combination Strategies ◽

Rational Drug ◽

Rational Combination ◽

Induced Apoptosis

Pazopanib is approved for treatment of advanced soft tissue sarcomas, but primary and secondary drug resistance limits its clinical utility. We investigated the molecular mechanisms mediating pazopanib resistance in human synovial sarcoma (SS) models. We found reduced cell sensitivity to pazopanib associated with inefficient inhibition of the two critical signaling nodes, AKT and ERKs, despite strong inhibition of the main drug target, PDGFRα. In the CME-1 cell line, overactivation of IGF1 and Insulin receptors (IGF1R/InsR) sustained AKT activation and pazopanib resistance, which was overcome by a combination treatment with the double IGF1R/InsR inhibitor BMS754807. In the highly pazopanib resistant MoJo cell line, NRASQ61R mutation sustained constitutive ERK activation. Transfection of the NRAS mutant in the pazopanib sensitive SYO-1 cell line increased the drug IC50. MoJo cells treatment with pazopanib in combination with the MEK inhibitor trametinib restored ERK inhibition, synergistically inhibited cell growth, and induced apoptosis. The combination significantly enhanced the antitumor efficacy against MoJo orthotopic xenograft abrogating growth in 38% of mice. These findings identified two different mechanisms of intrinsic pazopanib resistance in SS cells, supporting molecular/immunohistochemical profiling of tumor specimens as a valuable approach to selecting patients who may benefit from rational drug combinations.

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Therapeutic Advances in Myeloproliferative Neoplasms: The Role of New-Small Molecule Inhibitors

American Society of Clinical Oncology Educational Book ◽

10.14694/edbook_am.2012.32.175 ◽

2012 ◽

pp. 406-410 ◽

Cited By ~ 2

Author(s):

Srdan Verstovsek

Keyword(s):

Molecular Mechanisms ◽

Therapeutic Potential ◽

Myeloproliferative Neoplasms ◽

Janus Kinase ◽

Treatment Focus ◽

Rational Combination ◽

Short And Long Term ◽

Jak2 Inhibitors

Overview: The discovery that a somatic point mutation (JAK2V617F) in the Janus kinase 2 ( JAK2) is highly prevalent in patients with myeloproliferative neoplasms (MPNs) has been a crucial breakthrough in our understanding of the underlying molecular mechanisms of these diseases. Therefore, preclinical and clinical research in recent years has focused intensely on the development of new therapies targeted to JAK2. These efforts culminated in recent approval of ruxolitinib as the first official therapy for patients with intermediate- or high-risk myelofibrosis (MF). Therapy with JAK2 inhibitors substantially improves quality of life and reduces organomegaly in MF with or without JAKV617F mutation. Recent results suggest that patients with advanced MF may live longer when receiving therapy with ruxolitinib. However, JAK2 inhibitors do not eliminate the disease and new medications are needed to expand on the benefits seen with JAK2 inhibitors. Although many agents are still in the early stages of development, the wealth of publications and presentations has continued to support our growing understanding of the pathophysiology of MF as well as the potential short- and long-term outcomes of these new and diverse approaches to treatment. Focus of ongoing efforts is particularly on the improvements in anemia and fibrosis, as well as on rational combination trials of JAK2 inhibitors and other potentially active agents. Therapeutic potential and limitations of JAK2 inhibitors and other novel medications in clinical studies are reviewed.

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Characterization of 1,387 NSCLCs with MET exon 14 (METex14) skipping alterations (SA) and potential acquired resistance (AR) mechanisms.

Journal of Clinical Oncology ◽

10.1200/jco.2020.38.15_suppl.9511 ◽

2020 ◽

Vol 38 (15_suppl) ◽

pp. 9511-9511

Author(s):

Mark M. Awad ◽

Jessica Kim Lee ◽

Russell Madison ◽

Anthony Classon ◽

Jamie Kmak ◽

...

Keyword(s):

Donor Site ◽

Acquired Resistance ◽

Circulating Tumor Dna ◽

Acceptor Site ◽

Polypyrimidine Tract ◽

Comprehensive Overview ◽

Functional Sites ◽

Paired Samples ◽

Combination Strategies ◽

Rational Combination

9511 Background: METex14 SA are oncogenic drivers in NSCLC. Due to the numerous sites around ex14 that bind the spliceosome complex, many variations can result in deleterious alterations (alts). We present a comprehensive overview of these ex14 SA across 1,387 NSCLCs and characterized potential AR mechanisms. Methods: Hybrid-capture based comprehensive genomic profiling (CGP) was performed on samples from 60,495 NSCLC patients (pts). A scoring system was applied leveraging our large database of samples with METex14 SA to optimize accurate reporting of these variants. Paired samples were collected ≥ 60 days apart (median 462). Results: 1,393 METex14 SA were identified in samples (1,278 tissue, 109 circulating tumor DNA (ctDNA)) from 1,387 NSCLC pts (2.3%) spanning multiple functional sites: donor (42%), acceptor (4.7%), poly-pyrimidine tract (15%), acceptor and polypyrimidine tract (13%), D1010 (23%), Y1003 (2.1%), and whole exon deletions (0.3%). 6 samples (5 tissue, 1 ctDNA) harbored 2 METex14 SA, each including a mutation (mut) at the donor or acceptor site. MDM2 and CDK4 amplifications (amps) co-occurred in 32% and 19% of METex14 samples, respectively, but were more common with polypyrimidine tract (37% and 23%) vs donor site (32%, p = 0.07 and 18%, p = 0.07) alts. MET co-amp was present in 12% of cases and frequency did not significantly differ by functional site. 66 (4.8%) cases (57 tissue, 9 ctDNA) had known NSCLC co-drivers, including KRAS (68%) and EGFR (14%) mut, a subset of which may represent AR. Paired samples with a METex14 SA in the 1st sample were available for 36 pts. The METex14 SA was detected in the 2nd sample for 32 pts, excluding 3 with low ctDNA. 22/36 (61%) had reportable acquired alts detected including 9 with ≥1 acquired MET muts [D1228X (4), Y1230X (3), Y1003F (1), D1228A/E/H + L1195V (1)] and 3 with acquired MET amp. Other acquired alts included ERBB2 amp and mut (1 each), EGFR ex19ins (1), KRAS amp (1), PIK3CA mut (1), AKT2 amp (1) and others with unknown functional significance. Potential AR alts were present with primary METex14 SA spanning all functional sites. Conclusions: In a dataset of > 60,000 advanced NSCLCs, METex14 SA were present in 2.3% of cases, and represented 6 major subtypes. Among paired cases, potential AR mechanisms included secondary MET alts (33%), and acquired alts in EGFR, ERBB2, KRAS, and PI3K pathways. Acquired alts were independent of the type of METex14 SA. Characterizing common co-occuring may be critical for predicting responses to MET inhibitors and informing rational combination strategies.

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